1. Field of the Invention
The present invention relates to a method of forming a metal line in a semiconductor device and, more particularly, to a method of forming a metal line through a damascene process in the formation of a semiconductor device.
2. Discussion of Related Art
Nowadays, as the integration level in a semiconductor device is gradually higher integrated and densified, copper having a low resistance is used in a metal line that is formed through a damascene process.
A damascene process for forming a metal line according to a prior art will be described. A bottom anti-reflective coating (BARC) film is formed in a structure wherein an etch stop film and an interlayer insulating film are stacked, more than one time, on an interlayer insulating film into which a copper wiring metal is buried. A photoresist pattern, a pattern of a metal line trench, is formed in a given region of the BARC film. An etch process using the photoresist pattern as an etch mask is then performed to form a metal line trench.
Meanwhile, after forming the metal line trench, the photoresist pattern and the BARC film are removed. In this case, this is performed by a dry etch.
In case where the photoresist pattern and the BARC film are removed by the dry etch, however, there occurs a problem that the amount of polymer generated upon etching is increased.